Members' Notes:

This is apparently an unremarkable brownish moth. I haven't seen the adult but came upon a large (30-40) cluster of approximately 3/4"-long caterpillars somewhat lined up in ranks and files on the leafless lower part of a mature Smilax (greenbrier) vine in dense woods. When I went back the following day to take a picture I could only find the single specimen in the photo. It is reported to range up and down the East Coast from NY to Florida and west to Illinois and Texas. Smilax is the host plant.

http://roadsendnaturalist.wordpress.com/tag/turbulent-phosph...
A frequent defense strategy of many types of insects is to present a false head to would-be predators. This usually involves eye spots of some sort since we, and most vertebrate predators like birds, associate eyes with the head of an animal. By going after the head first, a bird is likely to immobilize its prey quickly and cut off any escape attempt.

A close look reveals the truth – the last three segments of the rear of the caterpillar are somewhat enlarged and have prominent white spots suggesting eyes. Ironically, the true head end of the larva also has false eye spots on the thorax. The true e... read moreyes, like those of most caterpillars, are diminutive and arranged in arcs on the side of the caterpillar’s true head capsule, which is tucked on the right side of the larva in the image above (note the presence of the short antennae and true legs on that end).

David Wagner ('Owlet Caterpillars of Eastern North America') states that
“the bold coloration is suggestive that the insect is chemically protected, although it remains to be shown if the Turbulent Phosphila is in fact unpalatable, or if its patterning is largely a ruse”.

Young caterpillars are gregarious feeders on various species of Greenbrier, but as they grow older, they become more solitary. Finding a group of them on the underside of a Greenbrier leaf or clumped on a vine is a caterpillar-lover’s (and perhaps graphic artist’s) delight.

The moth has two generations per year throughout much of our region and can often be found as late as November in the coastal plain.

Finding the Curve-lined Owlet caterpillar, and now these interesting larvae, on Greenbrier, gives me a reason to appreciate this often maligned vine.